Re: OSPF Equal cost balancing in serie 2500 routers

Discussion in 'Cisco' started by Aaron Woody, Oct 20, 2003.

  1. Aaron Woody

    Aaron Woody Guest


    I am not sure about performance on 2500 series routers, but I don't
    think your OSPF metric manipulation will do the trick. Usually the
    only way to load balance HSRP over both routers is to use "MHSRP" and
    to split your host over two gateways. MHSRP is defining two HSRP
    groups therefore providing two active Gateways on LAN, if one fails
    the other will take over for it. I have run into this design several
    times and eventually you have to decide which is more important...LAN
    redundancy or load balancing. I have included an article from Cisco on
    load sharing with HSRP.


    "Jose Manuel Payan del Rio" <> wrote in message news:<bmbkfs$9ks$>...
    > Hi all
    > I am using two Cisco 2501 routers to connect a building to our network
    > backbone, that I will name R1 and R2. Each router has a Frame Relay line
    > attached to one of its serial interfaces, that is, two FR lines (one for
    > each router).
    > At the network core, I have two Cisco 7500 routers, where I concentrate
    > traffic from many buildings, such as the one I am asking about. I will name
    > them F1 and F2.
    > The FR line connected to R1 has two PVCs, to F1 and to F2. So has the FR
    > line connected to R2. With this topology, R1 and R2 are directly connected
    > to both F1 and F2.
    > |- R1 ------------- F1
    > e| - -
    > t | - -
    > h| - -
    > | - -
    > |- R2 ------------ F2
    > To further complicate this, I am using HSRP, with a virtual ip address to
    > which clients at the access building direct their traffic. Only one router
    > (R1 and R2) is active.
    > R1 and R2 have only one ethernet port each, conected to an eth switch.
    > The issue is to get both FR lines balance outward traffic (from the building
    > clients' point of view).
    > I have suggested to use OSPF equal cost balancing but others engineers tell
    > me that 2500 do not support the topology I enclose below:
    > R1 serial 0 cost 40
    > R2 serial 0 cost 39
    > R1 et0 cost 1
    > R2 et0 cost 1
    > R1 has preempt mode and forced to be active (HSRP) when up, instead of R2.
    > ¿ Is this right ?
    > With this configuration I believe all clients will direct traffic to R1
    > (forced to be HSRP active router), and it will see two equal cost routes for
    > outgoing traffic. One is its own serial interface (cost 40) and the other,
    > through ethernet and R2 serial (1+39=40 cost).
    > ¿ I am right ? Other have tell me that it is a performance problem why 2500
    > cannot do this.
    > Regards
    Aaron Woody, Oct 20, 2003
    1. Advertisements

Want to reply to this thread or ask your own question?

It takes just 2 minutes to sign up (and it's free!). Just click the sign up button to choose a username and then you can ask your own questions on the forum.
Similar Threads
  1. NNTP Reader
    Jul 25, 2003
  2. Liam
    Bob by the Bay
    Oct 10, 2004
  3. mosfet
    Mar 3, 2006
  4. Martik
    Ron Martell
    Feb 11, 2005
  5. =?Utf-8?B?TkpU?=

    Internet Sharing: Equal upload speeds but un-equal download speeds

    =?Utf-8?B?TkpU?=, Sep 14, 2007, in forum: Wireless Networking
    Sep 15, 2007